Conference Coverage
Whatever the substance, adolescents’ abuse shares common links
In teens who are daily cigarettes smokers, use of alcohol, marijuana, and tobacco shares unique and common associations.
Las Vegas – When talking with adolescents and their families about marijuana use, Kevin M. Gray, MD, recommends embracing the complexity of the issue.
“Avoid polarizing this topic and avoid vilifying cannabis,” he advised at an annual psychopharmacology update held by the Nevada Psychiatric Association. “Take an interest in what they have to say about cannabis. Work in a gentle, nonconfrontational way where you avoid polarization and find some common ground where you can agree that maybe there’s some good and some bad [about cannabis], but the overwhelming evidence in adolescents is that there’s more harm than good with cannabis use, particularly recreationally.”
Dr. Kevin M. Gray
Dr. Gray, professor and director of child and adolescent psychiatry at the Medical University of South Carolina, Charleston, acknowledged that clinicians face a delicate balance between risk and benefit, even among Food and Drug Administration–approved medications. However, teens and families may struggle with these nuances, especially in light of the term “medical marijuana.” Some assume that “medical” implies “beneficial.” Others may equate “marijuana” with “natural,” which they may, in turn, equate with being “harmless.”
“Perception is critically important,” Dr. Gray said at an annual psychopharmacology update held by the Nevada Psychiatric Association.
Cannabis initiation typically occurs during adolescence, and rates of initiation and use are increasing. According to Dr. Gray, 55% of U.S. high school seniors have used marijuana, 23% use currently, and 6% use daily. “Those are the ones who have adverse outcomes,” he said. Young users are particularly prone to dependence symptoms and an inability to cut back their use. The odds of meeting criteria for cannabis use disorder are substantially greater in adolescent users than they are in adults regardless of time frame or intensity of use.
“In a dose-dependent manner, adolescent cannabis use is associated with adverse academic, occupational, cognitive, psychiatric, and substance use outcomes,” Dr. Gray said, adding that the average potency of delta-9-tetrahydrocannabinol (THC) in seized cannabis increased from 3% in 1992 to 11% in 2010. “Cannabis use in adolescence is associated with increased incidence and worsened course of psychotic, mood, and anxiety disorders. Serious cannabis-associated risks are well recognized and are particularly striking in adolescents. Adult-onset cannabis users may experience fewer adverse effects.”
Evidence-based psychosocial approaches for adolescents with cannabis use disorder include motivational enhancement therapy, which involves building rapport in a gentle way, with phrasing such as “Tell me what you like about marijuana use” and “What don’t you like about it?” Dr. Gray described motivational enhancement therapy as “a gentle nudge for behavior change” that serves as a bridge to cognitive-behavioral therapy, family therapy, and contingency management. “That said, long-term abstinence outcomes are generally poor,” he said. “People tend to go back to use.”
N-acetylcysteine (NAC) shows promise as a medication for adolescents with cannabis use disorder. NAC activates the cystine/glutamate exchanger and upregulates the GLT-1 receptor, which leads to reduction in reinstatement of drug seeking in animal models. One trial of NAC supported efficacy in 116 cannabis-dependent adolescents (Am J Psychiatry. 2012 Aug;169[8]:805-12). Led by Dr. Gray, the trial consisted of 8 weeks of active treatment on placebo or NAC 1,200 mg BID. All participants received weekly brief cessation counseling and twice-weekly contingency management. The researchers found that adolescents in the NAC group were more than twice as likely to submit a negative urine specimen during treatment than were their counterparts in the placebo group (odds ratio, 2.4; P = .029). In addition, those in the NAC group also were significantly more likely than were those in the placebo group to achieve end-of-treatment abstinence, which was defined as self-reported abstinence confirmed by negative urine testing throughout the last 2 weeks of treatment (OR, 2.3; P = .054).
A similarly designed adult trial indicated that adolescent findings did not translate to adults (Drug Alcohol Depend. 2017 Aug 1;177:249-57). “Whether this may be due to developmental differences in the course and phenomenology of cannabis use disorder, we don’t know,” Dr. Gray said. “For now, NAC remains the only pharmacotherapy with positive published intent-to-treat clinical trial abstinence findings for cannabis use disorder in adolescents. Positive adolescent findings must be replicated, but the necessary behavioral treatment platform must be clarified to translate successfully to real-world practice.”
Dr. Gray disclosed that he receives research funding from the National Institutes of Health.